The present application claims priority to U.S. Provisional Application No. 60/666,938, entitled RFID Tracking System and filed Mar. 29, 2005, and U.S. Provisional Application No. 60/773,634, entitled RFID Tracking System and filed Feb. 15, 2006, the entire disclosure of each of which is incorporated by reference herein.
Most item tracking systems in commercial settings can be classified as either a supply chain system or a manufacturing system. Manufacturing systems generally track items that remain within a facility, whereas supply chain systems generally track items that move into, through and out of a facility. One common supply change system is a distribution center conveyor system on which boxes or other packages from a receiving area are placed and transported to one or more stations at which the packages are identified, sorted and distributed to appropriate locations depending on the sortation. It is well known in such systems to employ bar code labels to the packages to thereby affix relevant information, for example manufacturer and package contents, that can be read by barcode scanners disposed along the conveyor. The scanner outputs information to a controller that associates the information with the package and outputs the associated information to a host system that can then manage the package's progression to its ultimate destination.
Barcode systems, although having developed to a high degree of reliability, suffer from certain inherent limitations in that they require a line of sight between the barcode scanner and the label, and the barcode label must be applied on the package so as to be optically readable. In contrast, radio frequency identification (RFID) tags do not require an optical line of sight for reading by an RFID reader.
Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.